Method and apparatus for cooling mine air



Sept. 20, 1932;

` A. S. RICHARDSON METHOD AND APPARATUS FOR COOLING MINE AIR Filed Nov. 23, 1951 2 Sheets-Sheet Sept. 20, 1932. A. s. RICHARDSON 1,878,542

METHOD AND APPARATS FOR COOLING MINE AIR I Filed Nov. 23, 1951 2 sheets-sneer 2 gva/vento@ Patented sept. 20,1932

; UNITED STATES vALLAN s. RICHARDSON, or EUTTE, MoNTANA METHOD AND APPARATUS `non COOLING MINE AIB.

Application mea November 23,1931. serial No. 576,857.

This invention relates to a method and apparatus for conditioning mine air andparkticularly to a method andapparatus by which the air may be cooled'iby heat exchange effeeted in proximity to the place or places in tclie mine workings where cooling is desire by this ings the entrance tothe mine that the., air becomes heated before reaching the workings. The present invention contemplates cooling the air at the place or places in the interior of the mine where cooling is desired by means of heat exchange apparatus disposed at these p aces. e

The use of a conventional refrigerating system in a mine is not generally practical due to the hazard attendant upon the use of the usual refrigerant mediums and the cost of operating a refrigerating system in the` interior of a mine. According to the present invention, an air cooling system,` for example, of the type employing spray coolers, is disposed at or near the workings to be cooled and the refrigerant medium employed by this system is cooled through heat exchange with a second system which has a means located exteriorly o f the mine.

In a specific embodiment, the invention maybe practised with certain desirable results by carrying out, in a single step, the cooling of the air by the primary refrigerant medium and the cooling of the primary refrigerant medium by the second vrefrigerant medium.- rf

An object of the presentinvention is to 40 provide a method and apparatusffor condiwhich is safe and inexpencooling tioning mine air sive to operate.

Another object of the invention is the provision of apparatus. for coolingv mine air, which apparatus is particularly adapted for use inV localities where the temperature of the surface air attains values below zero degrees Fahrenheit.

Other objects of the invention will appear 59 from the appended specification taken in con Heretofore, the air in mines has been cooled forcing cooled air through the mine, but method is impractical where the workto be cooled are so far removed froml nection with the accompanying drawings showing one form of the invention.

In the drawings:

Fig. 1 is a somewhat diagrammatic view showing the portion of the apparatus which ,55 is located at the mine entrance.

Fig. 2 -is a diagrammatic, plan View par.- tiallyu in cross-section, showing the portion of the apparatus which is located in proximity to the workings to be cooled.

Fig. 3 is a somewhat diagrammati'cfview, similar to Fig. 2, showing another modification of the invention, and

Fig. 4 is a diagrammatic, side elevational view, partially device according to Fig. 3.

l A cooling tower l of the air-cooled type is ddisposed adjacent lthe mine entrance and isJ connected, by means of pipes 2, 'extending into the mine, with a heat exchanger 4 of the 70 two-Huid type which is disposed in a recess in proximity to .the working to be cooled. A centrifugal pump 5 is provided forcirculatin a refrigerant medium,-such as calcium ch oride brine', between the heat exchangere and the cooling tower 1. Owing to the fact that the brine which has been warmed in the heat exchanger 4 has a lower specific gravity than that which has been cooled inthe cooling' tower 1, the convection effect is nearly sufi- ,cient to effect circulation ofthe brine and' only a small amount of power need be applied to the pump 5 to maintain the circulation of the brine.` L

Disposed in the path of flow of the mine air, which may be circulated by blowers (not shown) if circulation due to convection is not possible, is a spray cooler 6 which is connected to the heat exchanger 4.' The spray cooler 6 comprises four sections 7 'and 7 through 90 which a cooling liquid, preferablywater, is

circulated, in ya direction opposite to the direction of flow ofthe air. Each section comprises a header 8 from which depends a plurality of vertical nozzles 9 arranged to spray water into the air stream and a bafle 10 at the downstream side of the nozzles 8 to prevent the water from being carried along by the air stream. f x l [The intermediatesections 7 are provided 10p in cross-section, showing' 55 e `with three times as many nozzles 9' as'the outer The mine air is' drawn through the spray v cooler 6 and heat is taken up by the water which is circulated throu h the heat exchanger 4 where heat is trans erred from the wa: ter to the brine. The brine is circulated through the cooling tower 1 where heat is removed by a stream of atmospheric air which is drawn through the cooling tower 1.`

In Figs. 3 and 4 is shown a second embodiment of the invention. Disposed in the workings is a cooling chamber 12 having at one end a blower 13 for drawing the air to be cooled from the nearby workings, forcingy the air through the cooling chamber 12 and returning the air to the workings. Arranged in the path of air through the i chamber 12 are a plurality of sets of cooling coils 14,14 connected in series and connected by pipes 15, 16 to a cooling tower (not shown) similar to the tower 1 of Fig. 1 and disposed preferably at or near the entrance to the mine. A refrigerant is circulated through the sets of cooling coils 14, 14 in al direction counter to the direction of flow of air through the chamber 12.

Adjacent each set of cooling coils 14 and positioned to spray water or other li uid me- Adium thereon, is a set of sprayers 1 17 to each set of which is connected a pump 18 which in turn is connected toa sump 19 lying under the set of sprayers 17. The pump 18 draws water from the sump 19 and forces it from the sprayers 17 in the form of a curtain through which the air must pass in traveling through the chamber 12. On the downstream side of each set of coils is disposed a set of baffles which prevent'the water from being carried along by the air stream.

The operation of this form of the invention is as follows: -I

Mine air is drawn from the workings and is forced through the chamber 12 by the blower 13 where heat is transferred to the curtain of water and from the curtain of water to the refrigerant medium in the cooling coils 14, 14 heat is also transferred directlyfrom the air to the coils 14', 14. The heated refrigerant is then conducted through pipe 16 to the cooling tower as in the first form of the invention and the heat removed in a known manner and the refrigerant returned to the coils 14,14 throughpipe 15.

The use of a cooling medium such as calcium chloride brine has the advantages that the relatively high specific heat of the brine tioned, elimination of the possibility of explosions, absence of the presence of noxious y gases in the workings, and economy in the cost of renewal of the cooling medium. In view of the fact that the cooling system which includes the cooling tower, is a closed system, any cooling medium having the desired characteristics may be used inasmuch l,as none ofthe hazards encountered in the use of an open system will be met.

A further advantage of the present system is that the portion of the system wherein there is a large pressure head on the refrigerant medium is constituted by a completely closed circuit. This arrangement has the advantage that the head on one side of the system balances thehead on the other side of the system, whereby only a very small amount of power is necessary to effect circulation of the refrigerant medium, the power required being only that which is necessary to overcome friction of the refrigerant medium. Moreover, the circulation is still further assisted by the convection of the refrigerant medium. f

A further advantage is derived in that an eicient washing of the air is obtained which is of considerable importance in the conditioning of mine air. It is desirable to effect a very complete cleanino` of the air in order to eliminate the deleterious effect upon the health of the miners, caused by the extremely ine particles of matter suspended in the air .and also to eliminate the possibility of dust explosions.

I claim:

1. The methodl of conditioning mine air which comprises, contacting the air with water at the workings, circulating said water in heat exchange relation with a' second cooling` medium having a freezing point substantially lower than that of water to transfer heat from said water to said second cool-4 ing medium, circulating said second cooling medium in a closed circuit, and removing heat from said secondcoolingmedium at a point remote froin'the workings.

2. The invention as set forth in claim l, wherein said yheat transfer is carried out in the presence of the air which is being. conditioned.

, 3. Apparatus for conditioning mine air comprising; an air coolino 4and washing chamber disposed at the worlkings, means for circulating a liquid cooling medium comprising' water through said chamber in direct contact with the air to be conditioned, a closed refrigerant circuit containing a re-v frigerant medium having afreezing point substantially lower than that of Water, means disposed substantially at the surface for cooling said refrigerant medium, and heat eX- posed in said chamber.

change means 1n the vicinity of said Workrings for transferring heat from said water to said refrigerant medium.

4. The invention as set forth in claim 3,

wherein said heat exchange means is dis- 5. Apparatus for conditioning mine air 2 comprising, a closed refrigerant circulatingsystem containing a refrigerant 'medium and including a plurality of serially connected cooling coils disposed in said workings for circulating said refrigerailt medium in counter-current relation with the air to he cooled means for forcing said air past said coil, means at a point remote from said workings for cooling said refrigerant mediumfand means includinga separate, closed circuit for each of said, coils for circulating a second v refrigerant in contact with' said air and said coils simultaneously.A

6. Apparatus for cooling mineair comprising, a series of chambers disposed in the mine workings, means for forcing the air to be cooled through said chambers, a plurality of serially connected coils disposed one'in each chamber, means in each chamber for closed circuit through said` coils in countercirculating through the chamber a refriger- .ant medium in simultaneous contact with the air to be cooled and the coil, means for circulatlng a second refrigerant medlum -1n a current relation to the air to be eooledf'and means remote from said workings for cooling said second refrigerant.

In testimony whereof, I ax my signature.

' --ALLAN S. RICHARDSON. 

